CN113545165A

CN113545165A - Communication device, communication method thereof, information processing device, control method thereof, and program

Info

Publication number: CN113545165A
Application number: CN202080016900.9A
Authority: CN
Inventors: 藤森祐树
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 2019-02-28
Filing date: 2020-02-05
Publication date: 2021-10-22
Also published as: EP3934372A1; EP3934372A4; JP7273540B2; US20210368391A1; JP2023086978A; JP2020141300A; KR20210126689A; WO2020175051A1

Abstract

The communication device communicates a radio frame including a preamble and a data field of a physical layer (PHY). The preamble includes an L-STF (legacy short training field), an L-LTF (legacy long training field), an L-SIG (legacy signal field), an EHT-SIG-a (very high throughput signal a field), an EHT-STF (EHT short training field), and an EHT-LTF (EHT long training field), and the EHT-SIG-a includes subfields indicating whether data is transmitted in parallel from a plurality of communication devices to a common partner device.

Description

Communication device, communication method thereof, information processing device, control method thereof, and program

Technical Field

The present invention relates to a communication apparatus, a communication method thereof, an information processing apparatus, a control method thereof, and a program, and more particularly, to a communication control technique in a wireless LAN.

Background

In recent years, with an increase in the amount of data to be transmitted, communication technologies such as wireless LAN (local area network) have been developed. As a main communication standard of the wireless LAN, IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard series is known. The IEEE802.11 family of standards includes IEEE802.11a/b/g/n/ac/ax, and other standards. For example, in the latest standard ieee802.11ax, a technique has been standardized which uses OFDMA (orthogonal frequency division multiple access) to achieve high peak throughput up to 9.6 gigabits/second (Gbps) and additionally improves the communication speed in the case of congestion (see patent document 1).

On the other hand, in order to further improve the throughput, a research group named IEEE802.11EHT (very high throughput) has been formed as a subsequent standard of ieee802.11ax. In EHT, in order to achieve an improvement in throughput, it has been examined to allocate transmission data of a single STA (station) to a plurality of Access Points (APs) arranged while being spatially distributed, and to cause the access points to transmit data to the STA in parallel.

Reference list

Patent document

Patent document 1: japanese patent laid-open publication No. 2018-050133

Disclosure of Invention

Technical problem

It is useful to identify whether a STA receives a frame from a single AP or from multiple APs. On the other hand, in the conventional standard, it is assumed that the STA communicates with a single AP, but does not assume to communicate with a plurality of APs in parallel. For this reason, there is no mechanism configured to enable the STA to recognize that frames are transmitted in parallel from a plurality of APs.

Means for solving the problems

The present invention provides a technique that enables identification of whether a terminal of a wireless LAN communicates with a plurality of access points in parallel.

According to an aspect of the present invention, there is provided a communication apparatus characterized by comprising a transmission section for transmitting a radio frame including a preamble of a physical layer (PHY) and a data field, wherein the preamble includes an L-STF (legacy short training field), an L-LTF (legacy long training field), an L-SIG (legacy signal field), an EHT-SIG-a (very high throughput signal a field), an EHT-STF (EHT short training field), and the EHT-LTF (EHT long training field) and the EHT-SIG-a include sub-fields indicating whether data is transmitted in parallel to a common partner apparatus from another communication apparatus different from the communication apparatus.

Advantageous effects of the invention

According to the present invention, it is possible to recognize whether or not a terminal of a wireless LAN performs communication in parallel with a plurality of access points.

Other features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings. Note that the same reference numerals are used throughout the drawings to designate the same or similar components.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

Fig. 1 is a diagram showing an example of a network configuration;

fig. 2 is a block diagram showing an example of a functional configuration of an AP;

fig. 3 is a block diagram showing an example of a hardware configuration of an AP;

fig. 4 is a flowchart showing an example of a processing procedure performed in the AP;

fig. 5 is a sequence diagram showing an example of a processing procedure performed in a network;

fig. 6 is a diagram showing an example of a PHY frame structure of an EHT SU PPDU;

fig. 7 is a diagram showing an example of a PHY frame structure of an EHT ER PPDU; and

fig. 8 is a diagram showing an example of a PHY frame structure of an EHT MU PPDU.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the following examples are not intended to limit the scope of the claims of the present invention. A plurality of features are described in the embodiments, but not limiting the invention to all such features, and a plurality of such features may be appropriately combined. Further, in the drawings, the same reference numerals are given to the same or similar configurations, and redundant description thereof is omitted.

(network construction)

Fig. 1 shows an example of the configuration of a wireless communication network according to the present embodiment. The wireless communication network is configured to include access points (AP 102, AP 103, and AP 104) and terminals (STA 105, STA106, and STA 107), each of which is an EHT (very high throughput) device. Each of these devices is IEEE802.11EHT (very high throughput) compliant and configured to enable wireless communications compliant with the standard defined earlier in the IEEE802.11EHT standard. Note that the designation "IEEE802.11EHT" is provided for convenience and may be other designations when the standard is established, but this description and the appended claims are intended to cover all standards capable of supporting the processes described below. In the following description, an access point may be referred to as an "AP" and a station may be referred to as an "STA" without reference numerals without reference to a specific device or the like. Note that in fig. 1, a wireless communication network including three APs and three STAs is shown as an example, but the number of these communication devices may be two or less, or four or more. In fig. 1, a communicable area of a network formed by an AP 102, an AP 103, and an AP104 is indicated by a circle 101. Note that this communicable area may cover a larger area, or may cover only a smaller area. Further, although fig. 1 shows an STA supporting EHT, there may be an STA supporting only a standard (legacy standard) of a previous generation of EHT. Note that it is understood that EHT is an acronym for extremely High Throughput (Extreme High Throughput).

Note that in this example, the AP 103 and the AP104 may receive signals transmitted from the AP 102, and the AP 102 may receive signals transmitted from the AP 103 and the AP 104. However, the connection form is not particularly limited, and the AP 102, the AP 103, and the AP104 may be connected by wire or wirelessly. Note that the AP 103 and the AP104 may or may not be capable of transmitting/receiving signals to/from each other. Note that AP 102 to AP104 may form IEEE802.11EHT of a multi-AP coordination construct. That is, the APs 102 to 104 support a configuration in which a plurality of APs cooperatively communicate with one STA, as defined by IEEE802.11EHT. For example, STA105 may transmit/receive radio frames to/from cooperating

APs

103 and 104 in parallel. The STA105 may be configured to include a plurality of wireless LAN control units, for example, and transmit/receive radio frames to/from a plurality of APs using different radio channels. Note that STA105 may include a physical control unit capable of processing multiple frames received in parallel via multiple radio channels. That is, the STA105 has a configuration capable of physically processing a plurality of wireless communications in parallel logically using one or more control devices.

Here, APs that directly transmit/receive signals to/from the respective STAs, such as the AP 103 and the AP104, will be referred to as slave access points (S-APs). In addition, an AP capable of at least indirectly transmitting/receiving frames to/from each STA by issuing instructions to AP 103 and AP104, such as AP 102, will be referred to as a master access point (M-AP). Note that the M-AP may transmit/receive signals directly to/from STA 105. For example, AP 102 may function as an M-AP or an S-AP. In this case, for example, the AP 102 may issue an instruction to the AP 103 or the AP104 to cause it to transmit/receive a radio frame to/from the STA while performing transmission/reception of a radio frame between the own device and the STA 105. Note that when the S-AP is caused to transmit a radio frame, the M-AP may transmit transmission target data to the S-AP. However, the present invention is not limited thereto, and the S-AP may directly obtain the transmission target data from, for example, the internet. In addition, the M-AP may receive data from the S-AP, which may be received by the S-AP from the STA. The S-AP may transmit data received from the STA not to the M-AP but to a partner device of the STA.

Note that all APs in the same network may operate as M-APs and that it may be decided which AP should operate as an M-AP according to certain criteria. Note that the M-AP does not operate as an AP for beacon transmission or the like, and may merely perform the role of the M-AP to, for example, transmit instructions to the respective APs. In addition, each AP may operate as a plurality of S-APs by including a plurality of wireless LAN control units. The M-AP may be implemented as a logical function, and one physical AP may operate as one or more S-APs while operating as an M-AP.

An example of the configuration and processing of each of the AP 103 and the AP104, which are APs (S-APs) that directly transmit radio frames to STAs, will be described below.

(construction of AP)

Fig. 2 shows a functional configuration of the AP 103. Note that the AP104 has the same function. As an example, the AP 103 includes two sets of functional units (the wireless LAN control unit 201 and the antenna 207, and the wireless LAN control unit 206 and the antenna 208) configured to perform communication of the wireless LAN. The number of wireless LAN control units provided in the AP 103 is not limited to two, and may be one or three or more. The AP 103 further includes a frame generating unit 202, an M-AP signal analyzing unit 203, a UI control unit 204, and a storage unit 205.

The wireless LAN control unit 201 and the wireless LAN control unit 206 are each configured to include a circuit that transmits/receives radio signals to/from other wireless LAN devices (for example, other APs or STAs), and a program configured to control these. The wireless LAN control unit 201 and the wireless LAN control unit 206 each perform communication control of the wireless LAN, such as transmission of frames generated by the frame generation unit 202 and reception of radio frames from other wireless LAN devices in accordance with the IEEE802.11 standard series. The frame generation unit 202 generates radio frames transmitted by each of the wireless LAN control unit 201 and the wireless LAN control unit 208 based on the content analyzed by the M-AP signal analysis unit 203. Note that if the AP operates as an M-AP or does not cooperate with other APs, the frame generation unit 202 may generate a radio frame independently of the analysis by the M-AP signal analysis unit 203. If the own device (AP 103) operates as an S-AP, the M-AP signal analysis unit 203 interprets the contents of a radio frame received from the M-AP and to be transmitted to the STA. For example, with respect to a frame to be transmitted from the AP 103 to the STA105, information on how many APs transmitting frames to the STA105 exist, which channel is to be used for transmission/reception, and the like in addition to the AP 103 is obtained by the analysis.

The UI control unit 204 is configured to include hardware related to a User Interface (UI), such as a touch panel and buttons configured to accept operations of the AP 103 by a user (not shown) of the AP 103, and a program configured to control these. Note that the UI control unit 204 also has a function of presenting information to the user, such as display of images or audio output, for example. The storage unit 205 is configured to include a storage device such as a ROM (read only memory) or a RAM (random access memory) configured to store a program to be executed by the AP 103 and various data.

Fig. 3 shows a hardware configuration of each AP 103. As an example of its hardware configuration, the AP 103 includes a storage unit 301, a control unit 302, a function unit 303, an input unit 304, an output unit 305, a communication unit 306, and an antenna 307 and an antenna 308. Note that the AP104 and the STA may have the same hardware configuration. Note that since the STA has a general wireless LAN function, description of its functional configuration will be omitted.

The storage unit 301 is formed of one or both of a ROM and a RAM, and stores programs for performing various operations to be described later and various information such as communication parameters for wireless communication. Note that a storage medium such as a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, or a DVD may be used as the storage unit 301 in addition to the memory such as the ROM and the RAM.

The control unit 302 is formed of, for example, one or more processors such as a CPU and an MPU, an ASIC (application specific integrated circuit), a DSP (digital signal processor), an FPGA (field programmable gate array), or the like. Here, the CPU is an acronym of a central processing unit, and the MPU is an acronym of a microprocessing unit. The control unit 302 executes the program stored in the storage unit 301, thereby controlling the entire AP 103. Note that the control unit 302 can control the entire AP 103 by cooperation of a program stored in the storage unit 301 and an OS (operating system).

Further, the control unit 302 controls the function unit 303 to execute predetermined processing such as image capturing, printing, or projection. The functional unit 303 is hardware used by the AP 103 to execute predetermined processing. For example, if the AP 103 is a camera, the function unit 303 is an image pickup unit, and performs image pickup processing. For example, if the AP 103 is a printer, the function unit 303 is a printing unit and performs print processing. For example, if the AP 103 is a projector, the function unit 303 is a projection unit and performs projection processing. The data to be processed by the function unit 303 may be data stored in the storage unit 301, or may be data communicated with other APs or STAs via a communication unit 306 which will be described later.

The input unit 304 accepts various operations from the user. The output unit 305 performs various outputs for the user. Here, the output of the output unit 305 includes, for example, at least one of display on a screen, audio output by a speaker, vibration output, and the like. Note that both the input unit 304 and the output unit 305 may be implemented by one module, such as a touch panel.

The communication unit 306 controls wireless communication conforming to the IEEE802.11 standard series, or controls IP communication. The communication unit 306 is a so-called radio chip, which may itself comprise one or more processors and memory. In the present embodiment, the communication unit 306 may perform processing conforming to at least the ieee802.11ax standard. Further, the communication unit 306 controls the

antennas

307 and 308 to transmit and receive a radio signal for wireless communication. The AP 103 communicates content such as image data, document data, or video data with other communication devices via the communication unit 306. Each of the

antennas

307 and 308 is an antenna that can transmit and receive a signal in, for example, at least any one of a sub-GHz band, a 2.4GHz band, a 5GHz band, and a 6GHz band. Note that the frequency band (and the combination of frequency bands) to which the

antennas

307 and 308 are applicable is not particularly limited. Each of the

antennas

307 and 308 may be one antenna, or may be configured to include two or more antennas for MIMO (multiple input and multiple output) transmission/reception. Note that fig. 3 shows at least two

antennas

307 and 308, but the AP 103 may include only one antenna by using, for example, a multiband antenna supporting two or more of the above-described multiple bands. In addition, the AP 103 may include more antennas.

(treatment Process)

Next, examples of processing procedures performed by the above-described AP 103 and AP104 and processing procedures performed by the wireless communication network will be described. Fig. 4 and 5 show an example of a processing procedure of deciding that the AP 103 should operate as an S-AP and transmitting data to the STA105 in cooperation with the AP104 after information exchange with the AP 102.

In this process, first, it is decided which AP should operate as an M-AP (and which AP should operate as an S-AP) among the APs 102 to 104 (step S401). For example, parameters as APs are transmitted from the AP 103 to the AP 102(F501), and parameter comparison is performed, thereby deciding an AP that should operate as an M-AP. Note that AP parameters may also be sent from AP104 to AP 102 (not shown). Note that in this processing example, it is decided that AP 102 should operate as an M-AP, and that AP 103 and AP104 should operate as an S-AP. After that, the AP 102 operating as an M-AP notifies the

APs

103 and 104 operating as an S-AP of network information such as SSID and BSSID. The AP 103 and the AP104 receive the notified network information (step S402, F502). Note that if the roles of M-AP and S-AP are determined in advance, the processing of steps S401 and S402 and F501 and F502 may be omitted.

The AP 103 transmits a beacon according to the notified information (F503). Note that the beacon includes information indicating that a plurality of APs can cooperatively perform data transmission/reception to the connected STA. Note that the AP here includes logical APs, and one AP may include, for example, an AP operating in a 2.4GHz band and an AP operating in a 5GHz band. That is, data transmission/reception of a plurality of APs may include data transmission/reception of one physical AP capable of functioning as a plurality of logical APs. For example, the AP 103 adds a multi-AP information element in the beacon and transmits information including an SSID, a BSSID, and information of an operating wireless channel to be used by a plurality of APs capable of cooperative operation. The storage method and construction of these pieces of information are not limited to these, and the AP 103 may transmit similar pieces of information stored in a similar format. Upon receiving the beacon, the STA105 performs connection processing for at least one of the plurality of S-APs based on information included in the beacon (steps S403, F504). The connection process here includes processes such as authentication and association defined by the IEEE802.11 standards family. In the connection state of establishing connection with the STA105, the AP 103 notifies the connection state establishment of the M-AP and the STA together with the connection parameters (step S404, F505). At this time, if one physical AP serves as two logical APs, and each of them is set in a connection state with the STA, it is possible to inform the M-AP of this. Note that, in fig. 5, only the AP 103 is set in a connected state with the STA 105. However, the AP104 may also connect with the STA105 by transmitting a beacon and notify the M-AP (AP 102) of the connection state establishment. However, the present invention is not limited thereto, and for example, the STA may be set to be in a connected state with only one of the plurality of S-APs. In this case, for example, radio frames transmitted from other S-APs not in a connected state are processed by the STA as radio frames from the S-APs in a connected state. Note that even in the connected state of only one of the plurality of S-APs, the STA can recognize that the transmission source S-AP is different with respect to the radio frame from the S-AP. Note that, in the present embodiment, the preamble of the physical layer (PHY) of the radio frame is decoded, so that it can be recognized that signals are transmitted from a plurality of S-APs (i.e., a multi-AP coordination system is formed). That is, information representing that the multi-AP coordination system is formed is included in the PHY preamble of a frame received by the S-AP from the M-AP or a frame received by the STA from the S-AP (or M-AP). This allows a device receiving the frame to confirm whether a single or multiple APs transmit data to the STA. This will be described later.

The M-AP manages connection parameters of the S-AP in a connected state with the STA, thereby deciding transmission parameters based on the information and performing transmission data allocation later (F506). The S-AP is notified of the information of the transmission parameters decided by the M-AP, and the AP 103 decides its own transmission parameters based on the notified information (step S405). The connection parameters may include information on the transmission rate and error rate of the respective connection. The M-AP may allocate a large amount of transmission data to the S-AP having a high transmission rate connection and a small amount of transmission data to the S-AP having a low transmission rate connection. Accordingly, data transmission from the S-AP to the STA can be efficiently performed. In order to reflect the current connection situation, the connection parameters may be updated at a predetermined period of each S-AP and notified to the M-AP. After that, upon receiving the transmission data from the M-AP to the STA (steps S406, F507), the S-AP transmits the data to the STA (steps S407, F508).

The parallel transmission of such data from a plurality of S-APs to one STA can be performed by, for example, transmitting a trigger frame configured to trigger transmission from an M-AP to an S-AP after transmission of transmission target data from the M-AP to the S-AP. That is, in a state where preparation of transmission target data is completed, the S-AP immediately transmits data to the STA based on receiving a trigger frame from the M-AP. Note that when transmission target data is transmitted from the M-AP to the S-AP, information indicating the transmission timing of the data may be notified to the S-AP together with the transmission target data. In this case, the plurality of S-APs transmit the transmission target data at the instructed transmission timing, thereby transmitting the data to the STAs in parallel.

On the other hand, upon receiving data from the STA (step S408), the S-AP transmits the received data to the M-AP (step S409). Note that the order of data transmission and reception is an example, and data may be transmitted/received in a mode other than the modes shown in fig. 4 and 5, for example, so that data reception from the STA is performed before data is transmitted to the STA, for example.

(frame Structure)

Each of fig. 6 to 8 shows an example of PPDU (physical layer (PHY) protocol data unit) defined by the IEEE802.11EHT standard and transmitted in steps S406 and S407, F503, F507, and F508. Fig. 6 shows an example of an EHT SU (single user) PPDU, which is a PPDU for single user communication, and fig. 7 shows an example of an EHT MU (multi user) PPDU for multi user communication. Fig. 8 shows an example of an EHT ER (extended range) PPDU for long-distance transmission. When a communication area should be extended in communication between an AP and a single STA, an EHT ER PPDU is used.

The PPDU includes fields including an STF (short training field), an LTF (long training field), and a SIG (signal field). As shown in FIG. 6, the PPDU header includes L (legacy) -STF 601, L-LTF 602, and L-SIG 603 to ensure backward compatibility with the IEEE802.11a/b/g/n/ax standard. Note that each of the frame formats shown in fig. 7 and 8 includes: L-STF (L-STF 701 or L-STF 801), L-LTF (L-LTF 702 or L-LTF 802), and L-SIG (L-SIG 703 or L-SIG 803). Note that the L-LTF is arranged immediately after the L-STF, and the L-SIG is arranged immediately after the L-LTF. Note that each of the structures shown in fig. 6 to 8 further includes RL-SIG (repetitive L-SIG, RL-SIG 604, RL-SIG 704, or RL-SIG 804) arranged immediately after the L-SIG. In the RL-SIG field, the contents of the L-SIG are repeatedly transmitted. The RL-SIG is used to enable the receiving party to recognize that the PPDU conforms to the standard behind the ieee802.11ax standard and in some cases the RL-SIG may be omitted from IEEE802.11EHT. In addition, a field for enabling the receiving side to recognize that the PPDU conforms to IEEE802.11EHT standard may be provided instead of the RL-SIG. Note that the fields of the respective PPDUs are not necessarily arranged in the order shown in each of fig. 6 to 8, or may include new fields not shown in each of fig. 6 to 8.

The L-STF 601 is used for detection of PHY frame signals, AGC (automatic gain control), timing detection, and the like. The L-LTF 602 is used for highly accurate frequency/time synchronization, acquisition of propagation channel information (CSI: channel state information), and the like. The L-SIG 603 is used to transmit control information including information such as a data transmission rate and a PHY frame length. Legacy devices that comply with the IEEE802.11a/b/g/n/ax standard may decode the various legacy fields described above.

Each PPDU further includes more EHT-SIGs (EHT-SIG-A605, EHT-SIG-A705, EHT-SIG-B706, or EHT-SIG-A805) disposed immediately after the RL-SIG and used to transmit EHT control information. Each PPDU further includes an STF of the EHT (EHT-

STF

606, 707, or 806) and an LTF of the EHT (EHT-

LTF

607, 708, or 807). Each PPDU includes a

data field

608, 709, or 808 and a

packet extension field

609, 710, or 809 following these control fields. The portion including fields from L-STF to EHT-LTF of each PPDU is referred to as a PHY preamble.

Note that each of fig. 6 to 8 shows a PPDU capable of ensuring backward compatibility as an example. However, if backward compatibility is not necessarily ensured, for example, the legacy field may be omitted. In this case, for example, EHT-STF and EHT-LTF are used instead of L-STF and L-LTF to establish synchronization. Then, in this case, one of the plurality of EHT-LTFs after the EHT-STF and EHT-SIG fields may be omitted.

The EHT-SIG-A605 and 805 included in the EHT SU PPDU and the EHT ER PPDU include EHT-SIG-A1 and EHT-SIG-A2, respectively, which are required to receive the PPDU, as shown in tables 1 and 2 below. In the present embodiment, a "multi-AP" subfield representing whether data is transmitted from a plurality of APs to an STA is included in the EHT-SIG-a 1. In addition, the EHT-SIG-A705 of the EHT MU PPDU shown in FIG. 7 includes EHT-SIG-A1 and EHT-SIG-A2 required for receiving the PPDU, as shown in tables 3 and 4 below. In this embodiment, a "multi-AP" subfield representing whether data is transmitted from a plurality of APs to an STA is included in the EHT-SIG-a 2. For example, if data is transmitted from multiple APs to a STA, 1 is stored in the "multiple AP" subfield. If data is sent from a single AP to a STA, a 0 is stored in the "multi-AP" subfield. Note that the configurations of table 1 to table 4 are merely examples, and for example, in the EHT SU PPDU and the EHT ER PPDU, information of the multi-AP may be notified at a position other than the 15 th bit of the EHT-SIG-a1 field. Also, in the EHT MU PPDU, the information of the multi-AP may be notified at a position other than the 8 th bit of the EHT-SIG-a2 field. In addition, the information of the multi-AP may specify whether data is transmitted from a plurality of physical APs to the STA, or may specify whether data is transmitted from a plurality of logical APs to the STA. For example, even if data is physically transmitted from one AP to the STA, if data is logically transmitted from a plurality of APs to the STA, 1 may be designated in the multi-AP subfield.

[ Table 1]

[ Table 2]

[ Table 3]

[ Table 4]

Note that the EHT-SIG-B706 of the EHT MU PPDU includes common field information as shown in table 5 and user block field information as shown in table 6, which are necessary for receiving the PPDU.

[ Table 5]

[ Table 6]

As shown in fig. 6, in the user block field, a user field is included, and information of each user is stored. The format of the user field varies depending on whether data is transmitted to a plurality of users through OFDMA or data is transmitted through MU-MIMO. Table 7 shows a user field when data is transmitted by OFDMA, and table 8 shows a user field when data is transmitted by MU-MIMO.

[ Table 7]

[ Table 8]

Note that the contents of these subfields are the same as those defined by the ieee802.11ax standard, and a description thereof will be omitted here.

As described above, in the frame structure of PPDUs (EHT SU PPDU, EHT ER PPDU, and EHT MU PPDU) used in the IEEE802.11EHT standard, it is possible to notify an STA whether a single AP or a plurality of APs transmit data. That is, the S-AP may inform the STA whether there is an AP that transmits data to a common partner device (STA) in parallel, in addition to its own device. Also, by transmitting this frame, the M-AP may inform the S-AP whether there are other S-APs (or whether the M-APs transmit data in parallel) that transmit data in parallel to a common partner device (STA). At this time, for example, if the STA performs the connection process only for one AP, the STA can recognize that there is another AP with which the STA should communicate through a radio channel different from the AP that performed the connection process, that is, through a radio channel different from a radio channel in which the own device operates. Note that the radio channel here may include, for example, a frequency channel or a spatial channel. For example, upon confirming the PHY preamble and confirming the reception of data from a plurality of APs, the STA may operate to designate a plurality of APs as data transmission sources. The STA may acknowledge, for example, the sender address in the MAC (medium access control) header of each of the plurality of data streams, thereby obtaining information of the plurality of APs. Also, for example, if information of a plurality of APs is acknowledged, the STA may individually transmit acknowledgement (ACK/NACK) to each AP. In addition, if the radio quality of data for certain APs degrades, the STA may notify any one AP (e.g., M-AP) that should be excluded from the multi-AP coordination objective. This makes it possible to maintain high radio quality communication in the STA. In addition, in the STA or the AP, the user may be notified via the UI of information representing whether or not data is transmitted from a plurality of APs to the STA. In addition, if the own device does not support multi-AP coordination and receives a PPDU transmitted from a plurality of APs on behalf of data, the STA may immediately discard the PPDU. Accordingly, in the STA, information after the multi-AP subfield is not unnecessarily decoded for PPDUs to which the own device cannot be applied. Therefore, power consumption can be suppressed. Note that the present invention can be implemented not only by the AP 102 to AP104 and the STA105 to STA107 as communication devices, but also by an information processing device (e.g., a radio chip) configured to generate the above-described PHY preamble.

Note that in the example described above, the multi-AP subfield is prepared as a 1-bit field to indicate whether data is transmitted from a plurality of APs to the STA. However, the present invention is not limited thereto. For example, the multi-AP subfield may be prepared as a field of two or more bits to display the number of APs transmitting data to the STA. For example, if a 2-bit field is prepared, it may be represented by "00" for data transmitted from one AP, "01" for data transmitted from two APs, "10" for data transmitted from three APs, and "11" for data transmitted from four or more APs. Similarly, when a field of three or more bits is prepared, it can represent a larger number of APs.

The present invention can provide a program for implementing one or more functions of the above-described embodiments to a system or an apparatus through a network or a storage medium by processing, and cause one or more processors in a computer of the system or the apparatus to read out and execute the program. The invention may also be implemented by a circuit (e.g., an ASIC) for performing one or more functions.

The present invention is not limited to the above-described embodiments, and various changes and modifications can be made within the spirit and scope of the present invention. Therefore, for the public to appreciate the scope of the present invention, the appended claims are presented.

This application claims priority from japanese patent application No. 2019-036402, filed on 28.2.2019, which is incorporated herein by reference.

Claims

1. A communication device, characterized in that the communication device comprises:

a transmitting part for transmitting a radio frame including a preamble and a data field of a physical layer (PHY),

wherein the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF), and

the EHT-SIG-A includes a subfield that indicates whether data is to be transmitted in parallel to a common partner device from another communication device different from the communication device.

2. A communication device, characterized in that the communication device comprises:

a receiving part for receiving a radio frame including a preamble and a data field of a physical layer (PHY),

wherein the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-A includes a subfield that indicates whether data is transmitted in parallel from a plurality of other devices, and

in case the subfield indicates that data is transmitted in parallel from a plurality of other devices, data from one of the plurality of other devices is included in the data field.

3. The communication device of claim 1 or 2, wherein the sub-field is a 1-bit sub-field in the EHT-SIG-a, the 1-bit sub-field indicating whether the device transmitting data in parallel comprises a single device or a plurality of devices.

4. A communication device according to claim 1 or 2, wherein the sub-field is an at least 2-bit sub-field in the EHT-SIG-a, the at least 2-bit sub-field indicating the number of devices transmitting data in parallel.

5. The communication device of any of claims 1-4, wherein the sub-field includes information based on a number of physical devices transmitting the data.

6. The communication device of any of claims 1-4, wherein the sub-field includes information based on a number of logical devices sending the data.

7. The communication device of claim 2, wherein the communication device is configured to notify a user of information indicating whether data is received from the plurality of other devices based on information in the subfield.

8. An information processing apparatus characterized by comprising:

a generation section for generating a radio frame including a preamble of a physical layer (PHY),

the EHT-SIG-a includes a subfield that indicates whether data is to be transmitted in parallel from a plurality of communication devices to a common partner device.

9. A communication method performed by a communication device, the communication method comprising:

a transmitting step of transmitting a radio frame including a preamble and a data field of a physical layer (PHY),

10. A communication method performed by a communication device, the communication method comprising:

a receiving step of receiving a radio frame including a preamble and a data field of a physical layer (PHY),

in case the subfield indicates that data is transmitted in parallel from the plurality of other devices, data from one of the plurality of other devices is included in the data field.

11. A control method executed by an information processing apparatus, characterized by comprising:

a generation step of generating a radio frame including a preamble of a physical layer (PHY),

the EHT-SIG-A includes a subfield that indicates whether data is to be transmitted in parallel from the plurality of communication devices to a common partner device.

12. A program configured to cause a computer to function as one of the communication apparatus defined in any one of claims 1 to 7 and the information processing apparatus defined in claim 8.